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CABI Europe-UK 2 What’s New In Biological Control of Weeds species. Recently CABI Europe–UK has begun surveys of wild ginger in India. India is a long-standing member country of CABI, and CABI has an offi ce in New Delhi, making them ideally placed to conduct the surveys. “India is not the easiest place to work in, especially with recent changes in legislation,” reports Djami Djeddour of CABI. New laws aimed at promoting conservation of biological diversity and equitable sharing of benefi ts arising out of the use of biological resources currently makes it extremely diffi cult to export any species, dead or alive, even for identifi cation purposes. “This remains a major hurdle to be overcome if the project is to succeed,” cautioned Djami. This type of impediment to biocontrol projects is unfortunately becoming increasingly common. In India nonnationals may not collect any material from the fi eld without prior notifi cation and authorisation from the National Biodiversity Authority or appropriate state institutes, so CABI has initiated communications and collaborations with Damage caused by unknown insect on white ginger. a network of Indian scientists including forestry institutes, national bureaux and research centres to facilitate this and other biocontrol projects. The initial survey in October 2008 was timed to coincide with the purported fl owering period to make it easier to fi nd and identify the plants (as the keys for this genus generally use fl oral characteristics), and to avoid the summer monsoon period. Identifying Hedychium species in the fi eld still proved to be quite a challenge as most plants had in fact moved on to the fruiting stage and had to be identifi ed by their leaves and stems and through local knowledge. Since Hedychium species also hybridise quite readily, molecular studies will be needed to clarify how the plants found in India compare with the weed populations needing to be controlled in New Zealand and Hawai’i. In particular when looking for prospective pathogens, which can be host-specifi c in the extreme, it may be necessary to look in places that provide a good match to fi nd suitable strains. The three wild ginger species of interest were located in a range of habitats from roadsides and gardens through to forests. “It was extremely heartening to see that all were being subjected to attack from a suite of natural enemies (both insects and pathogens) with damage being infl icted on all parts of the plant,” reports Djami. The wild ginger was growing in equilibrium with native vegetation and not exhibiting any of the invasive traits that we see in New Zealand or Hawai’i. Close relatives, such as edible ginger and cardamom, were often growing in close proximity to the wild ginger allowing observations Issue 48 May 2009 Pathogen having a serious impact on yellow ginger. of the natural fi eld host-range of the prospective control agents, and allowing some insect species to be discounted immediately for lacking suffi cient specifi city. However, most of the specimens collected still need to be identifi ed and, given that they can’t be taken out of India, this may take some time. As well as identifying the material already collected, further surveys are needed to ensure that nothing is overlooked. Normally several surveys are needed to pick up all prospective agents and it is important to look across a wide geographic distribution as well as in diff erent seasons. Early monsoon (June–July) has been identifi ed as the best time for the next survey, so don’t forget to pack your raincoats guys! This project is funded by the National Weed Biocontrol Collective (New Zealand), and The Nature Conservancy of Hawai’i, the United States Geological Survey, and the Pacifi c Islands Ecosystem Research Centre. CABI Europe-UK
What’s New In Biological Control of Weeds Issue 48 May 2009 A Stitch in Time? We have been making some headway over the last 12 months in the uphill battle against Chilean needle grass (Nassella neesiana) in Australia and New Zealand. During this time a new infestation of this damaging grass was found in North Canterbury, confi rming fears that despite comprehensive measures to contain it, it was only a matter of time before the weed became more widespread, and increasing the urgency to fi nd better control methods. Through great perseverance David McLaren (Department of Primary Industries, Australia) has fi nally secured permission to import into Argentina the grass species we need to include in host range testing. This means that they can now be tested by Freda Anderson and her team of assistants (CERZOS-UNS) for their susceptibility to the most promising potential agent, a rust fungus called Uromyces pencanus. Unfortunately, they will need to do this testing in a plant containment facility at Castelar, a town near Buenos Aires, rather than in their own glasshouse at Bahía Blanca. Still, for a while there it looked as though host range testing would have to be done outside of Argentina. “While there will be lots of logistical diffi culties with having to move ourselves and our equipment 700 km north, it is still a much better option than shifting the testing to South Africa or the UK!” observed Freda. Further good news was received in January: David’s application to the Australian Government for a further 12 months of funding, for the 2009 calendar year, was successful. Due to the delays in getting the seed to Freda she was unlikely to be able to complete the host range testing by the end of 2009, but fortunately, New Zealand was able to “step into the breach”. Freda was thrilled to hear that funding pledged by the National Biocontrol Collective for the 2009/10 fi nancial year will run until the end of June 2010. “I was having sleepless nights about getting everything fi nished between June (when the fi rst test plants should be ready for inoculation) and December,” said Freda, “so it is a huge relief to know we have a few more months up our sleeves.” New Zealand funding also allowed Jane Barton to visit Freda again in February to help with the project. On this trip Jane carried with her a very precious parcel: Chilean needle grass seeds from Marlborough and Auckland. Freda had found previously that the isolate of Uromyces pencanus that worked best against Australian Chilean needle grass did not attack populations from Auckland or the Hawke’s Bay, but she had been unable to test it against material from Marlborough populations, due to the diffi culties in getting seed into Argentina. “I can now get on with that task,” said Freda “and we are also ‘bulking up’ two other rust strains to test against New Zealand plant material.” Jane delivered the seed to Dr Eduardo Botto, a new and very helpful collaborator who works at the quarantine facility in Castelar. While work with Uromyces pencanus has been accelerating, the second most promising candidate, the rust Puccinia graminella, has been extremely uncooperative. A particularly hot and dry summer was followed by an unusually cold winter and this seems to have led to the local extinction of P. graminella at the only fi eld site within striking distance of Bahía Blanca; other sites are hundreds of kilometres north. This rust mostly produces a spore stage known as aeciospores, which do not store very well. Consequently, Freda has run out of spores to use for experiments and is unable to do any further work on this organism until it can be re-collected from the fi eld. At least this will allow Freda to concentrate solely on U. pencanus for a while, and for once there appear to be no further obstacles to the completion of host range testing of that fungus. Touch wood!!! Jane Barton is a contractor to Landcare Research. Chilean needle grass seed on a quad bike that has gone through infested paddocks in the Blind River area of Marlborough. Marlborough District Council 3
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